Buoyancy (Weight of a barbell underwater)

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SUMMARY

The discussion focuses on calculating the force a bodybuilder must exert to lift a 20-kg steel barbell underwater. The buoyant force (Fb) is determined using the formula Fb = Density x Volume x Gravity, resulting in a buoyant force of approximately 24.92 N. To find the total force exerted by the bodybuilder, the calculation combines the buoyant force with the weight of the barbell, leading to a total force of 498.35 N. This demonstrates the principles of buoyancy and force calculation in a fluid environment.

PREREQUISITES
  • Understanding of buoyancy principles
  • Familiarity with basic physics formulas (Fb = Density x Volume x Gravity)
  • Knowledge of unit conversions (kg to N)
  • Ability to calculate volume from mass and density
NEXT STEPS
  • Research the Archimedes' principle and its applications
  • Learn about fluid dynamics and its impact on weight perception
  • Explore advanced buoyancy calculations in different fluids
  • Study the effects of submerged weight on resistance training
USEFUL FOR

This discussion is beneficial for fitness trainers, sports scientists, and anyone interested in the physics of weightlifting and buoyancy in aquatic environments.

wallace13
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A bodybuilder is holding a 20-kg steel barbell above her head. How much force would she have to exert if the barbell were lifted underwater?Fb= Density x Volume x Gravity
Density= mass/volume
7860= 20/ V

V= .00254 m^3
Fb= 1000 x .00245 x 9.81
Fb= 24.9174 N
 
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You've found the buoyant force, which is the force exerted by the water. But what's the force that she has to exert?
 
I've never done this type of problem wouldn't it just be mass*bouancy force 24.917 * 20 kg =498.35N
 

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